You can verify that the FCC has canceled the license by looking up the FCC license call sign data at http://wireless.fcc.gov/uls.
If the license has been canceled, the FCC will show the license status as CANCELED.

A close relative may make a preferential request to the FCC that the callsign be assigned to them for their own callsign under the "Vanity Program," if they hold the required license. His local Club may also make a request for the call in honor of the deceased member, with the families permission and supporting letter to the FCC at the address above.